ESD materials

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Conductive ESD bag with a network card inside
ESD shoes

ESD materials are special plastics which are designed to reduce static electricity so it will protect electrostatic-sensitive devices (ESD) or contain flammable liquids or gases.

Materials

ESD materials are generally subdivided into categories with related properties: Anti-Static, Conductive, and Dissipative.[1]

Ohms Per Square Material Description
> 1012
Insulative
Insulators and Base Polymers. Not an ESD material
109 to 1012
Anti-Static
Initial charges are suppressed
106 to 109
Dissipative
No or low initial charge. Prevents discharge to or from human contact
103 to 106
Conductive
No initial charge. Provides path for charge to bleed-off
1 to 103
Shielding
10-3 to 1
Carbons
Carbon powders and fiber
< 10-3
Metals

Insulative

Insulative materials prevent or limit the flow of electrons across their surface or through their volume. Insulative materials have a high electrical resistance and are difficult to ground, thus are not ESD materials. Static charges remain in place on these materials for a very long time.

Anti-Static

Anti-static materials are generally referred to as any material which inhibits triboelectric charging. This kind of charging is the buildup of an electric charge by the rubbing or contact with another material. One type of anti-static packaging material is commonly referred to as Pink Poly. It is a clear pink (hot pink) polyethylene that is available as a film for bags, bubble pack, or foam.

Dissipative

Dissipative materials allow the charges to flow to ground more slowly in a more controlled manner than with conductive materials.

Conductive

Conductive materials have a low electrical resistance, thus electrons flow easily across the surface or through these materials. Charges go to ground or to another conductive object that the material contacts.

See also

References

  1. ↑ Anti-Static and Conductive Plastics; Boedeker Plastics.

Further reading

  • The Wiley Encyclopedia of Packaging Technology; 1st Edition; Kit. L. Yam; John Wiley & Sons; 1353 pages; 2009; ISBN 978-0-470-08704-6.
  • Plastics Additives Handbook; 6th Edition; Zweifel, Maier, Schiller; Hanser Publications; 1222 pages; 2009; ISBN 978-1569904305.
  • Handbook of Conducting Polymers; 3rd Edition; Skotheim and Reynolds; CRC Press; 1680 pages; 2007; ISBN 978-1574446654.
  • Conductive Polymers and Plastics: In Industrial Applications; 1st Edition; Larry Rupprecht; Elsevier; 293 pages; 1999; ISBN 978-0815516569.
  • Plastics Additives and Modifiers Handbook ; 1st Edition; Jesse Edenbaum; Springer; 1136 pages; 1992; ISBN 978-0442234508.
  • Metal-Filled Polymers: Properties and Applications; 1st Edition; S.K. Bhattacharya; CRC Press; 376 pages; 1986; ISBN 978-0824775551.

External links

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